QuEChERS-高效液相色谱-串联质谱法快速测定鸡肉中氟虫腈及其代谢物

建立一种QuEChERS-高效液相色谱-串联质谱法,快速测定鸡肉中氟虫腈及其3种代谢产物(氟甲腈、氟虫腈砜及氟虫腈亚砜)的方法。鸡肉样品经乙腈分散,DisQuE提取管提取和DisQuE净化管净化后,采用液相色谱-串联质谱定量测定,选择性多反应监测模式检测。在0.5~20ng/mL线性范围内,氟虫腈及其代谢产物的回归方程均呈良好的线性关系,R2>0.999,在添加水平为1.0、5.0、10.0μg/kg时,平均回收率为75.2%~89.9%,相对标准偏差(RSD)为0.8%~9.2%,方法检出限为0.5μg/kg,定量限为1.0μg/kg。该方法简便快捷,灵敏度和准确度均较高,精密度较好,适用于鸡肉中氟虫腈及其代谢产物残留量的检测。     

气相色谱法和高效液相色谱-串联质谱法测定 鸡蛋中氟虫腈及代谢物残留

目的建立适用于鸡蛋中氟虫腈及其代谢物(氟虫腈砜、氟虫腈硫醚和氟甲腈)残留的电子捕获检测器-气相色谱法和高效液相色谱-串联质谱检测方法。方法通过Qu ECh ERS提取盐包(CEN EN-15662)用乙腈提取目标化合物,借助固相萃取(PRiMEHLB)作为净化手段,采用气相和液相质谱进行监测。结果气相色谱法和高效液相色谱-串联质谱法中4种分析物的定性限(limit of detection,LOD)分别为0.1μg/kg和0.02μg/kg;定量限(limit of quantification,LOQ)分别为0.5μg/kg和0.1μg/kg,在0.1~10.0μg/L和0.1~5.0μg/L范围内线性关系良好,相关系数r~2均大于0.999。在2.5,5和10μg/kg 3种加标浓度下,平均回收率分别为80.8%~103%和87.4%~101%,相对标准偏差(relative standard deviation,RSD,n=6)分别为0.84%~5.62%和0.87%~4.40%。结论该方法步骤简便、可靠、稳定,适合于蛋类中氟虫腈及其代谢物残留的痕量分析。     

QuEChERS-液相色谱-串联质谱法测定南瓜中噻虫胺和氟啶虫胺腈的残留量

该研究建立了QuEChERS-液相色谱-串联质谱法同时测定南瓜中噻虫胺和氟啶虫胺腈残留量的分析方法。样品中的噻虫胺和氟啶虫胺腈经乙腈均质提取和基质分散萃取法净化,净化后的样液经0.22μm滤膜过滤后,采用液相色谱-串联质谱法测定。采用C18色谱柱分离,电喷雾离子化、正离子扫描方式和动态多反应监测模式检测,基质匹配标准溶液外标法定量。噻虫胺在2.5～100μg/L(氟啶虫胺腈在0.5～20μg/L)的范围内线性关系良好,相关系数分别为0.9994和0.9988。噻虫胺在5、10和50μg/kg(氟啶虫胺腈在1、2和10μg/kg)的3个添加水平的平均回收率在88.5%～111.2%之间,相对标准偏差(RSD,n=6)在1.12%～6.92%。噻虫胺和氟啶虫胺腈的方法定量限分别为1.0μg/kg和5.0μg/kg。该方法快速简便、灵敏度高、重现性好,可满足南瓜中噻虫胺和氟啶虫胺腈的残留检测要求。     

液相色谱-串联质谱法测定鸡蛋中氟虫腈及其代谢物的残留量

建立一种采用液相色谱-三重四级杆质谱测定鸡蛋中氟虫腈及其代谢物(氟甲腈、氟虫腈砜和氟虫腈硫醚)的快速筛查方法。鸡蛋样品经乙腈和正己烷提取,C18固相萃取柱净化,Shim-pack XR-ODSⅢ色谱柱(2.0 mm i.D×150 mm,2.1μm)分离,以乙腈-5 mmol/L乙酸铵(0.02%甲酸)水溶液为流动相,梯度洗脱,外标法定量。采用液相色谱-三重四级杆串联质谱动态多反应监测模式,以负离子采集进行定性筛查和定量分析。结果表明,氟虫腈及其代谢物在0～50μg/L质量浓度范围内线性关系良好,相关系数R2均大于0.999。以10倍信噪比确定各药物的定量限(LOQ),氟虫腈及其代谢物的定量限为0.3～0.6μg/kg。在0.5、5.0和10.0μg/kg添加水平下,氟虫腈及其代谢物的平均回收率为92.3%～105.1%,相对标准偏差(RSD)为1.2%～8.6%。该方法简便、快速、灵敏,适用于鸡蛋中氟虫腈及其代谢物的快速筛查和定量检测。     

气相色谱-串联质谱正离子模式测定食品中氟虫腈和溴虫腈残留

建立食品中氟虫腈和溴虫腈残留的气相色谱-串联质谱(GC-MS/MS)分析方法。方法 试样经乙腈提取, N-丙基乙二胺(PSA)固相萃取柱(SPE)净化,采用GC-MS/MS以正离子模式多反应监测(MRM)定性、定量测定氟虫腈和溴虫腈。结果 该方法在5～50μg/L浓度范围内呈线性,相关系数r均大于0.998。氟虫腈和溴虫腈的添加回收率分别为78.2%～102.5%和77.0%～104.1%,RSD分别为6.8%～15.2%和6.9%～17.1%,二者的检出限(LOD)均为5μg/kg,定量限(LOQ)均为10μg/kg。结论 气相色谱-串联质谱法正离子模式是简便、快速、准确测定食品中氟虫腈和溴虫腈残留分析方法。     

超高效液相色谱-串联质谱法测定果蔬中氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯残留量

建立超高效液相色谱-串联质谱同时测定蔬菜和水果中氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯残留量的分析方法。样品经乙腈均质提取,混合使用乙二胺-N-丙基硅烷和十八烷基硅烷基质分散净化剂净化,以C18色谱柱分离待测物,采用电喷雾离子化,正离子扫描和动态多反应监测模式检测,基质匹配标准溶液外标法定量。氟啶虫胺腈在0.2～100?μg/L之间,Pyrifluquinazon在0.02～10?μg/L之间,螺虫乙酯在0.1～10?μg/L之间的范围内线性关系良好,相关系数均大于0.999?0。在4个添加水平进行氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯添加回收率实验,平均添加回收率在79.9%～103.9%之间,相对标准偏差在3.3%～8.8%之间。氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯的方法定量限分别为0.334、0.040?5?μg/kg和0.378?μg/kg,检出限分别为0.100、0.012?2?μg/kg和0.133?μg/kg。该方法快速简便、定量准确,可满足多种蔬菜和水果中氟啶虫胺腈、Pyrifluquinazon和螺虫乙酯3?种杀虫剂的残留检测要求。     

鸡蛋中氟虫腈及其代谢物残留分析方法

采用超高效液相色谱-串联质谱技术,以鸡蛋为研究对象,建立一种高效测定鸡蛋中氟虫腈及其代谢物残留测定方法。样品用乙腈提取,并通过固相萃取技术对样品进行净化处理,供超高效液相色谱-串联质谱仪进行检测。实验结果表明,该方法能够有效地分离和测定氟虫腈及其代谢物残留。在3 个不同的添加水平（0.005、0.010、0.020 mg/kg）下,4 种农药的回收率范围为81.3%～92.5%,相对标准偏差均低于5.5%。;在0.001～0.050 μg/mL 浓度范围内,线性关系良好,相关系数均大于0.990 4;氟虫腈、氟甲腈、氟虫腈砜与氟虫腈亚砜的检出限分别为0.001、0.002、0.002、0.002 mg/kg。该方法准确、灵敏、快速,可满足对鸡蛋中氟虫腈、氟甲腈、氟虫腈砜与氟虫腈亚砜4 种药物残留的检测需要。     

固相萃取-高效液相色谱-串联质谱法测定茶叶中啶虫脒、吡虫啉和氟虫腈残留量

目的建立茶叶中吡虫啉、啶虫脒和氟虫腈三种农药残留的固相萃取-高效液相色谱-串联质谱测定方法。方法样品用水浸泡,乙腈提取,经石墨化碳-氨基复合固相萃取小柱净化,采用Agilent Eclipse AAA色谱柱分离,以0.1%乙酸水溶液和乙腈为流动相梯度洗脱,正、负离子切换扫描,多反应监测(MRM)模式检测,外标法定量。结果在3个添加水平下,吡虫啉、啶虫脒和氟虫腈的平均回收率分别为78.8%~91.5%,81.3%~92.8%,和72.8%~90.0%;相对标准偏差分别为2.6%~10.6%,3.7%~6.6%和3.6%~7.4%。啶虫脒、吡虫啉和氟虫腈的检出限均为0.5μg/kg,定量限为2μg/kg。结论建立的方法简便、快速,灵敏度高,可满足出口茶叶中吡虫啉、啶虫脒和氟虫腈残留同时检测的要求。     

气相色谱-负化学源-串联质谱法测定动物源食品中氟虫腈及其4种代谢产物残留量

建立动物源食品(鸡蛋、鸡肉、鸡肝)中氟虫腈及其4种代谢产物(氟甲腈、氟虫腈砜、氟虫腈硫醚、酰胺氟虫腈)残留量的气相色谱-负化学源-串联质谱(gas chromatography-negative chemical ionization-tandem mass spectrometry,GC-NCI-MS/MS)测定方法。样品经乙腈(正己烷饱和)提取后,采用改进的QuEChERS净化和GC-NCI-MS/MS的多反应监测模式检测,基质匹配工作曲线法定量。实验结果表明,氟虫腈及其4种代谢产物在1~100μg/L质量浓度范围内线性良好,线性系数均大于0.999 0,氟甲腈、氟虫腈和氟虫腈硫醚定量限(RSN≥10)为0.5μg/kg,氟虫腈砜和酰胺氟虫腈定量限为1.0μg/kg。在2.0、10.0、20.0μg/kg加标水平下,回收率在80.2%~108.7%之间,相对标准偏差为3.8%~10.2%。该方法灵敏度高、准确性好,能够满足动物源食品中氟虫腈及其4种代谢产物残留量的测定。     

固相萃取-UPLC-MS/MS法测定牛奶中氟虫腈及其代谢物残留量

建立一种固相萃取-超高效液相色谱-串联质谱法同时测定牛奶中氟虫腈及其代谢物(氟甲腈、氟虫腈砜、氟虫腈硫醚)的分析方法。牛奶样品经提取和盐析,Oasis PRiME HLB固相萃取柱通过式净化后,以乙腈-水为流动相,HSS T3色谱柱(2.1mm×100 mm,1.8 μm)进行色谱分离,在电喷雾负离子模式下,多反应监测(MRM)方式进行测定,外标法定量。结果表明,氟虫腈及其代谢物在0.05~5.0 μg/L浓度范围内均呈良好的线性关系,相关系数r≥0.9976,方法检出限为0.01 μg/kg,定量限为0.05 μg/kg。在浓度分别为0.5、1、10 μg/kg加标水平下,4种化合物的回收率范围为80.6%~101%,相对标准偏差范围为1.0%~6.1%。该方法简单快捷、准确可靠,适用于牛奶中氟虫腈及其代谢物的同时测定。     

Textural Properties of Cold-set Gels Induced from Heat-denatured Whey Protein Isolates

A 9% whey protein (WP) isolate solution at pH 7.0 was heat-denatured at 80°C for 30 min. Size-exclusion HPLC showed that native WP formed soluble aggregates after heat-treatment. Additions of CaCl2 (10–40 mM), NaCl (50–400 mM) or glucono-delta-lactone (GDL, 0.4–2.0%, w/v) or hydrolysis by a protease from Bacillus licheniformis caused gelation of the denatured solution at 45°C. Textural parameters, hardness, adhesiveness, and cohesiveness of the gels so formed changed markedly with concentration of added salts or pH by added GDL. Maximum gel hardness occurred at 200 mM NaCl or pH 4.7. Increasing CaCl2 concentration continuously increased gel hardness. Generally, GDL-induced gels were harder than salt-induced gels, and much harder than the protease-induced gel.     

Occurrence of bisphenol-F-diglycidyl ether (BFDGE) in fish canned in oil

The levels of bisphenol-F-diglycidyl ether (BFDGE) were quantified as part of a European survey on the migration of residues of epoxy resins into oil from canned fish. The contents of BFDGE in cans, lids and fish collected from all 15 Member States of the European Union and Switzerland were analysed in 382 samples. Cans and lids were separately extracted with acetonitrile. The extraction from fish was carried out with hexane followed by re-extraction with acetonitrile. The analysis was performed by reverse phase HPL C with fluorescence detection. BFDGE could be detected in 12% of the fish, 24% of the cans and 18% of the lids. Only 3% of the fish contained BFDGE in concentrations considerably above 1mg/kg. In addition to the presented data, a comparison was made with the levels of BADGE (bisphenol-A-diglycidyl ether)analysed in the same products in the context of a previous study.     

Contribution of European research to risk analysis

The European Commission's, Quality of Life Research Programme, Key Action 1—Health, Food & Nutrition is mission-oriented and aims, amongst other things, at providing a healthy, safe and high-quality food supply leading to reinforced consumer confidence in the safety of European food. Its objectives also include the enhancing of the competitiveness of the European food supply. Key Action 1 is currently supporting a number of different types of European collaborative projects in the area of risk analysis. The objectives of these projects range from the development and validation of prevention strategies including the reduction of consumers risks; development and validation of new modelling approaches; harmonization of risk assessment principles, methodologies, and terminology; standardization of methods and systems used for the safety evaluation of transgenic food; providing of tools for the evaluation of human viral contamination of shellfish and quality control; new methodologies for assessing the potential of unintended effects of genetically modified (genetically modified) foods; development of a risk assessment model for Cryptosporidium parvum related to the food and water industries; to the development of a communication platform for genetically modified organism, producers, retailers, regulatory authorities and consumer groups to improve safety assessment procedures, risk management strategies and risk communication; development and validation of new methods for safety testing of transgenic food; evaluation of the safety and efficacy of iron supplementation in pregnant women; evaluation of the potential cancer-preventing activity of pro- and pre-biotic ('synbiotic') combinations in human volunteers. An overview of these projects is presented here.     

低温带皮菜籽粕微粉的不同粒级部分的功能特性

为研究低温带皮菜籽粕微粉的不同粒级部分的功能特性,以经低温脱脂的带皮菜籽粕为原料,经微粉碎后筛分成212~425μm、150~212μm和106~150μm的3个不同粒级的微粉样品,检测这些样品的吸水性、吸油性、乳化性和乳化稳定性、蛋白质体外消化率。结果表明:1 3个不同粒级的微粉样品之间的粗纤维含量存在显著差异,表明三者的结构组成成分有一定差异。23个微粉样品的乳化活性和乳化稳定性随粒度级别的减小而显著增加(P0.01)。33个微粉样品的蛋白质体外消化率随粒度级别的减小而显著增加(P0.01)。4不同粒级带皮菜籽粕微粉样品的吸水性与吸油性受其结构组成物质不同和粒度的双重影响,与粒度的相关性不明显。     

Microbiology of food taints

Fresh and processed foods are often spoilt by the presence of undesirable flavours and odours caused by microbial action. The aim of this paper is to review the current knowledge of microbiologically induced taints that occur in a wide range of foodstuffs, including meats, poultry, fish, crustaceans, milk, dairy products, fruits, vegetables, cereals and cereal products. Examples have been chosen where the compounds responsible for the taint have been identified and sufficient data obtained to demonstrate the involvement of microorganisms. However, in some cases the full identity of the causative organism may not have been elucidated. The types of microorganisms covered by this review include bacteria, fungi, yeasts, actinomycetes and cyanobacteria. Although cyanobacteria do not in general infect foods, their presence in aqueous systems and water supplies can lead to off-flavours in aquatic organisms and processed foodstuffs. Several examples of each of these processes are discussed. Wherever possible, the likely biosynthetic pathway used by the microorganism to produce the offending compound in a foodstuff is indicated.     

Analysis for organic residues from aids to polymerization used to make plastics intended for food contact

Polymers intended for food contact use have been analysed for organic residues which could be attributed to a range of substances employed as polymerization aids (e.g. initiators and catalysts). A wide range of polymers was extracted with solvents and the extracts analysed by gas chromatography-mass spectrometry (GC-MS). The overwhelming majority of substances identified were not derived from aids to polymerization but were oligomers, additives and adventitious contaminants. However, a small number of substances were identified as initiator residues. These included tetramethylsuccinonitrile (TMSN) which was observed in two polymers and it derived from recombination of two azobisisobutyronitrile (AIBN) initiator radicals. Methyl benzoate, benzoic acid, biphenyl and phenyl benzoate were detected in one poly(methyl methacrylate) sample and in two polyvinylchlorides and they are thought to be derived from benzoyl peroxide initiator. TMSN was subsequently targeted for analysis of poly-(methyl methacrylate) plastics using proton nuclear magnetic resonance spectrometry (¹     

Tests of potential functional barriers for laminated multilayer food packages. Part II: Medium molecular weight permeants

Experiments were performed to characterize the kinetics of the permeation of different medium molecular weight model permeants: bisphenol A, warfarin and anthracene, from liquid paraffin, through a surrogate potential functional barrier (25 microns-thick orientated polypropylene--OPP) into the food simulants olive oil and 3% (w/v) acetic acid. The characterization of permeation kinetics generally observed the permeation models previously reported to explain the experimental permeation results obtained for a low molecular weight group of model permeants. In general, the model permeants exhibited behaviour consistent with their relative molecular weights with respect to (a) the time taken to attain steady-state permeation into the food simulant in which they were more soluble, (b) their subsequent steady-state permeation rates, and (c) their partition between liquid paraffin and the OPP membrane.     

The development of reference materials for paralytic shellfish poisoning toxins in lyophilized mussel. I: Interlaboratory studies of methods of analysis

This paper describes the first part of a project undertaken to develop mussel reference materials for Paralytic Shellfish Poisoning (PSP) toxins. Two interlaboratory studies were undertaken to investigate the performance of the analytical methodology for several PSP toxins, in particular saxitoxin (STX) and decarbamoyl-saxitoxin (dc-STX) in lyophilized mussels, and to set criteria for the acceptance of results to be applied during the second part of the project: the certification exercise. In the first study, 18 laboratories were asked to measure STX and dc-STX in rehydrated lyophilized mussel material and to identify as many other PSP toxins as possible with a method of their choice. In the second interlaboratory study, 15 laboratories were additionally asked to determine quantitatively STX and dc-STX in rehydrated lyophilized mussel and in a saxitoxin-enriched mussel material. The first study revealed that three out of four postcolumn derivatization methods and one pre-column derivatization method sufficed in principle to determine STX and dc-STX. Most participants (13 of 18) obtained acceptable calibration curves and recoveries. Saxitoxin was hardly detected in the rehydrated lyophilized mussels and results obtained for dc-STX yielded a CV of 58% at a mass fraction of 1.86 mg/kg. Most participants (14 out of 18) identified gonyautoxin-5 (GTX-5) in a hydrolysed extract provided. The first study led to provisional criteria for linearity, recovery and separation. The second study revealed that 6 out of 15 laboratories were able to meet these criteria. Results obtained for dc-STX yielded a CV of 19% at a mass fraction of 3.49mg/kg. Results obtained for STX in the saxitoxin-enriched material yielded a CV of 19% at a mass fraction of 0.34mg/kg. Saxitoxin could not be detected in the PSP-positive material. Hydrolysis was useful to confirm the identity of GTX5 and provided indicative information about C1 and C2 toxins in the PSP-positive material. The methods used in the second interlaboratory study showed sufficiently consistent analysis results to undertake a certification exercise to assign certified values for STX and dc-STX in lyophilized mussel.     

The Ministry of Environmental Protection Issued "Feasible Technology Guidelines for Pollution Prevention and Control in Wood Pulping Process of the Paper Industry (Trial)" and Two Other Guiding Technical Documents

On December 27t＂, 2013, the Ministry of Environmenta Protection announced that, in order to implement ＂The Environmental Protection Law of the People＇ s Republic of China＂, improve the working system in environmenta protection technologies, and promote technologica advancement in pollution prevention, the Ministry of Environmental Protection sponsored the formulation of three guiding technical documents including ＂Feasible Technology Guidelines for Pollution Prevention and Contro n Wood Pulping Process of the Paper Industry （Trial）＂     

1~(st) Intelli-Tissue~ EcoEc Tissue Machine Supplied by PMP Group Successfully Put into Operation in China

正On April 29th,2014,Intelli-Tissue EcoEc tissue machine supplied by PMP Group successfully put into operation at Hebei Xuesong Paper Co.,Ltd.,this is the first such kind of paper machine of PMP Group in China.